Simulations Based Approach for Vehicle Idle NVH Optimization at Early Stage of Product Development 2011-01-1591
The noise and vibration performance of diesel fueled automotives is critical for overall customer comfort. The stationary vehicle with engine running idle (Vehicle Idle) is a very common operating condition in city driving cycle. Hence it is most common comfort assessment criteria for diesel vehicles. Simulations and optimization of it in an early stage of product development cycle is priority for all OEMs. In vehicle idle condition, powertrain is the only major source of Noise and Vibrations. The key to First Time Right Idle NVH simulations and optimization remains being able to optimize all Transfer paths, from powertrain mounts to Driver Ear.
This Paper talks about the approach established for simulations and optimization of powertrain forces entering in to frame by optimizing powertrain mount hard points and stiffness.
Powertrain forces optimized through set process are further used to predict the vehicle passenger compartment noise and steering vibrations. The process for optimization of transfer paths to reduce the passenger compartment NVH is discussed. SUV with body over frame construction was selected for study.
Advanced diagnostic techniques like Transfer Path Analysis (TPA), Modal Contribution Analysis (MCA) and Panel Contribution Analysis (PCA) were performed to arrive at First Time Right optimization.
The component and system level weak points were identified as a part of performance optimization. This helped in quick and First Time Right design modifications. The study resulted in significant improvement in vehicle Idle NVH along with considerable saving in computational cost & time.